package upload2;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;
import java.text.DecimalFormat;
import java.util.concurrent.atomic.AtomicLong;

/**
 * 文件断点续传加分段上传线程
 * @author wzztestin
 *
 */
/**
 * 文件断点续传加分段上传线程
 * @author wzztestin
 *
 */
public class DownFileFetch extends Thread {
	DownFileInfoBean siteInfoBean = null; // 文件信息 Bean
	long[] nStartPos; // 开始位置
	long[] nEndPos; // 结束位置
	DownFileSplitterFetch[] fileSplitterFetch; // 子线程对象
	long nFileLength; // 文件长度
	boolean bFirst = true; // 是否第一次取文件
	boolean bStop = false; // 停止标志
	File tmpFile; // 文件下载的临时信息
	DataOutputStream output; // 输出到文件的输出流
	boolean fileflag; // 是本地上传还是远程下载的标志
	File downfile; // 本地文件下载
	int splitter = 0;
	
	AtomicLong readySize = new AtomicLong(0);
	
	/**
	 * 下载上传文件抓取初始化
	 * @param bean
	 * @throws IOException
	 */
	public DownFileFetch(DownFileInfoBean bean) throws IOException {
		siteInfoBean = bean;
		/**
		 * File.separator windows是\,unix是/
		 */
		tmpFile = new File(bean.getSFilePath() + File.separator + bean.getSFileName() + ".info");
		
		fileflag = bean.getFileflag();
		downfile = bean.getDownfile();
		this.splitter = bean.getNSplitter();
		nFileLength = getFileSize();
		
		if (tmpFile.exists()) {
			bFirst = false;
			// 读取已下载的文件信息
			read_nPos();
		} else {
			nStartPos = new long[bean.getNSplitter()];
			nEndPos = new long[bean.getNSplitter()];
		}

	}

	public void run() {
		// 获得文件长度
		// 分割文件
		// 实例 FileSplitterFetch
		// 启动 FileSplitterFetch 线程
		// 等待子线程返回
		try {
			if (bFirst) {
				if (nFileLength == -1) {
					DownFileUtility.log("File Length is not known!");
				} else if (nFileLength == -2) {
					DownFileUtility.log("File is not access!");
				} else {
					for (int i = 0; i < nStartPos.length; i++) {
						nStartPos[i] = (long) (i * (nFileLength / nStartPos.length));
					}
					for (int i = 0; i < nEndPos.length - 1; i++) {
						nEndPos[i] = nStartPos[i + 1];
					}
					nEndPos[nEndPos.length - 1] = nFileLength;
				}
			}
			// 启动子线程
			fileSplitterFetch = new DownFileSplitterFetch[nStartPos.length];
			for (int i = 0; i < nStartPos.length; i++) {
				fileSplitterFetch[i] = new DownFileSplitterFetch(siteInfoBean.getSSiteURL(), siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName() + "_" + i, nStartPos[i], nEndPos[i], i, fileflag, downfile, bFirst, readySize);
				DownFileUtility.log("Thread " + i + " , nStartPos = " + nStartPos[i] + ", nEndPos = " + nEndPos[i]);
				fileSplitterFetch[i].start();
			}
			// 下载子线程是否完成标志
			boolean breakWhile = false;
			while (!bStop) {
				write_nPos();
				DownFileUtility.sleep(500);
				breakWhile = true;
				for (int i = 0; i < nStartPos.length; i++) {
					if (!fileSplitterFetch[i].bDownOver) {
						breakWhile = false;
						break;
					} else {
						write_nPos();
					}
				}
				if (breakWhile) {
					break;
				}
			}
			hebinfile(siteInfoBean.getSFilePath() + File.separator + siteInfoBean.getSFileName(), splitter);
			DownFileUtility.log("文件下载结束！");
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 获得文件长度
	 * @return
	 */
	public long getFileSize() {
		int nFileLength = -1;
		if (fileflag) {
			try {
				URL url = new URL(siteInfoBean.getSSiteURL());
				HttpURLConnection httpConnection = (HttpURLConnection) url.openConnection();
				httpConnection.setRequestProperty("User-Agent", "NetFox");
				int responseCode = httpConnection.getResponseCode();
				if (responseCode >= 400) {
					processErrorCode(responseCode);
					// represent access is error
					return -2;
				}
				String sHeader;
				for (int i = 1;; i++) {
					sHeader = httpConnection.getHeaderFieldKey(i);
					if (sHeader != null) {
						if (sHeader.equals("Content-Length")) {
							nFileLength = Integer.parseInt(httpConnection.getHeaderField(sHeader));
							break;
						}
					} else {
						break;
					}
				}
			} catch (IOException e) {
				e.printStackTrace();
			} catch (Exception e) {
				e.printStackTrace();
			}
			DownFileUtility.log(nFileLength);
		} else {
			try {
				File myflie = downfile;
				nFileLength = (int) myflie.length();
			} catch (Exception e) {
				e.printStackTrace();
			}
			DownFileUtility.log(nFileLength);
		}
		return nFileLength;
	}

	/**
	 * 保存下载信息（文件指针位置）
	 */
	private void write_nPos() {
		try {
			output = new DataOutputStream(new FileOutputStream(tmpFile));
			output.writeInt(nStartPos.length);
			for (int i = 0; i < nStartPos.length; i++) {
				output.writeLong(fileSplitterFetch[i].nStartPos);
				output.writeLong(fileSplitterFetch[i].nEndPos);
			}
			output.close();
			
			String percent = new DecimalFormat("#0.00").format((double)readySize.get() / nFileLength * 100);
			System.out.println("下载百分比：" + percent + "%");
			
		} catch (IOException e) {
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 读取保存的下载信息（文件指针位置）
	 */
	private void read_nPos() {
		try {
			DataInputStream input = new DataInputStream(new FileInputStream(tmpFile));
			int nCount = input.readInt();
			nStartPos = new long[nCount];
			nEndPos = new long[nCount];
			for (int i = 0; i < nStartPos.length; i++) {
				long startPos = input.readLong();
				nStartPos[i] = startPos;
				readySize.getAndAdd(startPos - i * (nFileLength / nStartPos.length));
				nEndPos[i] = input.readLong();
			}
			input.close();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 输出错误信息
	 * @param nErrorCode
	 */
	private void processErrorCode(int nErrorCode) {
		DownFileUtility.log("Error Code : " + nErrorCode);
	}

	/**
	 * 停止文件下载
	 */
	public void siteStop() {
		bStop = true;
		for (int i = 0; i < nStartPos.length; i++)
			fileSplitterFetch[i].splitterStop();
	}

	/**
	 * 合并文件
	 * @param sName
	 * @param splitternum
	 */
	private void hebinfile(String sName, int splitternum) {
		File file = new File(sName);
		if (file.exists()) {
			file.delete();
		}
		
		RandomAccessFile saveinput;

		try {
			saveinput = new RandomAccessFile(sName, "rw");
			for (int i = 0; i < splitternum; i++) {
				File splitFile = new File(sName + "_" + i);
				
				RandomAccessFile input = new RandomAccessFile(splitFile, "r");
				byte[] b = new byte[1024];
				int nRead;
				while ((nRead = input.read(b, 0, 1024)) > 0) {
					write(saveinput, b, 0, nRead);
				}
				input.close();
				
				splitFile.delete();
			}
			
			new File(sName + ".info").delete();
			
			DownFileUtility.log("file size is " + saveinput.length());
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		
	}

	/**
	 * 写文件
	 * @param b
	 * @param nStart
	 * @param nLen
	 * @return
	 */
	private int write(RandomAccessFile oSavedFile, byte[] b, int nStart, int nLen) {
		int n = -1;
		try {
			oSavedFile.seek(oSavedFile.length());
			oSavedFile.write(b, nStart, nLen);
			n = nLen;
		} catch (IOException e) {
			e.printStackTrace();
		}
		return n;
	}
}
